Treatment of gas distribution systems



TREATMENT OF GAS DISTRIBUTION SYSTEMS John R. Skeen, Philadelphia, Pa.,assignor to The United Gas Improvement Company, a corporation ofPennsylvania Application July 22, 1939, Serial No. 285,942

6 Claims. (Cl. 48-190) Thls application is a continuation-inpart of myeopending application Serial Number 236,822, flled October 24, 1938, andpertains generally to the treetment of the interiors of gas mains orother gas enclosures with a lqud mixture containing a non-cyclic highbolling ali phatic alcohol and monophenyl ether of ethylene glycol.

Systems for the distribution of gas include conduits r mains which areusuaily laid underground, and which comprise sections of pipe Joinedtogether by means of welding, by means of packed joints, by means ofscrew joints, or otherwise, I

'Ihe welded joint is a more recent development and is used chiefly toJpn pipe sections of steel or ron, other than cast ron.

Older mains are usually made up of cast ron pipe sections joined bymeans of bel] and spigot or other similar joints. These joints areusually packeci with hemp, jute, flax or other cellulosic materie] whichin turn is backed up with leed or cement or other material in a wellknown marmer.

Over a period of years the water condensed from wet gas together withother constituents of the gas such as carbon dioxide, hydrogen sulphide,hydrocyanic acid, naphthalene. and so forth, have in many nstances,caused extensive corroslon of the interior walls of the mains. Theproducts of corrosion have accumulated on the walls of the mains and, inmany instances, large quantities have become disconnected and havecollected along the bottom.

Due to the presence of relatively large quanti tes of moisture, largelyresponsible for the corroson in the first instance, the products ofcorrosion Ware maintained in 21 Wet condition and dd hot: tend to formdust in any appreciable quantity.

T'herefore, until high pressure distribution came into practice, andwhile the use of natural gas or naturel gas mixtures vvere lesswiclespread, very little clifficulty was experiencecl with the formationof dust in mains from the products of corrosion.

In ether words, as long as a man is uscd for distributing ordinary wetmanufactured gas very little trouble With dust resulting from corrosionis experienced. However, when the servic is changed over to amanufactured gas of 1ovv moisture content, or over te natural gas ornatural gas mixtures which are characterized by very low moisturcontent, the moisture on and in the corrosion products dries out andsuch products become a serious source of dust.

'I'he presence of conscierable quantities of dust in the gas flowingthrough the mains of a distribution system is very undesirable becausedust tends to clog up customer service connec tions, interferes with theproper operation of meters, and tends to clog up burners and pilotoutlets.

Under extreme conditions corrosion may be so severe as to form a serieusobstrueton in the man tself by reducing ts eflectlve cross-sectionalarea such as by the accumulation of dust in ples in the main.

A number of methods of correcting dust troubles have been proposed andused.

For instance, excavations have been made at suitably spaced points alongthe main, say, every 300 feet, the main severed at each excavation andthe accumulation removed mechanicaly.

This has been done by drgging a ball of chan back and forth through thedisconnected section and increasing the size of the hall as more andmore of the produets of corroson have been removed. In some instances, acutter has been substituted for the ball of 'chain.

In another method a compressor is conformed to function as a suctondevice for sucking air through the disconnected man section, and thedust is collected in a bag in a marmer customary in the operation of theordnary vacuum cleaner.

It will be apprecated that eitherof the foregoing methods of overcomingdust troubles is very expensve in view of the immense amount of laborinvolved. Furthermore, both methods put the main out of service durngthe treatment.

The use of steam for dust laying has the disadvantage that the depostedmoisture dries out as soon as steamng is stopped. As far as I am awarethe same also applies to the fogging of oil nto the mains, since the oilwhlch it has been necessary to use for successful foggng has had to beso light as to make t appreciably volatile.

Furtherrnore, since the corrosion products comprise not only ordnary ronrust but also a varety of other compounds resultng from the action ofhvdrogen sulficle, hydrocyanic acid, naphthalcne, and other corrosivesubstances, the

problem of wetting down the dust, of wetting the and operate to excludemeny types of treating substances from contact with sources of dustend/or with joint packings where treatrnent of the letter is desirecisuch as with a lo uid capa.ble of swelling nemp and jute to the sameextent as water.

A-eature of the invention is to provide en improved dust laying end/orjoint sealing cornposition which possesses sufficent solvent power withrespect to tar, resin anci gum to ceuse the treating oonstituent orconstituents of the composition zo wet and be absorbed by accumulationsof dust end/or cellulosie fiber packing Wth sufficient rapidity orpraeticable purposes.

Another feature of the invention is to provide a dust laying end/orjoint seaiing composition having improved wettng quelities not only orter, resin end. gum, but also for the metal the main wells.

Another feature of the nvention is te provide a new article ofmanufacture and a process or makng the same.

Other features of the invention will become, more apparent to persom,skilled in the art as the specficetion proceeds.

I have diseovered that a liquid mixture cornprising a non-cyclic highboiling alphatic alcohol end monophenyl ether of ethylene glycol isexcellently adapted (a) te wet, hold end/or bind dust particles end tocoat dust sources; (b) to soften or dissolve ter, resin end/or gum Whichmay cover dust sources or form incrustations wr,h dust deposits; and (0)to spread and climb upon the walls of the gas main am:l throughout thesources of dus'r.

The non-cyclic high bolling alphatic alcohol may be 0ne which is capableof swelling cellulosc fiber paoking to the serne extent as water of.which ethylene glycol, dethylene glycol, mono methyl ether of ethyleneglycol, mono methyl ether of diethylene glycol and glycerine ereoutstending examples.

The tar resin and gum penetrating power of monophenyl ether of ethyleneglycol and its wetting and elirnbing aeton greatly improve the action ofsuch tieating lquids by dissolving or softening ter resins end gum enthe pecking ami assisting the swellng agent to climb and wet thepacking.

Any desired quantity of my mono phenyl ether of ethyene glycol may beaclrnixed with such dust 1aying end/or cellulosic fiber swelling iiquidsaccording to the results desired, such as from 5 to 20% in the case ofcellulosc fiber swelling liquids.

When more drastc treatrnent is required to penetrate incrustationglerger percentages are recommended.

'I'he treating liquid mey be applecl to the interior surface of a pipesection during or after the assembly of the pipe sections to form themain. 'I'hs mey be accomplished in any desred marmer such as byspraying, brushing, or otherwise.

If the main is alreedy in service, sections of the main may be "blockedo by means of inflated bags or other means, and the sections thencompletely filled with the liquid after which the liquid een be dreWnoff end re-useci.

On the other hand, the liquid may be sprayeci into the gas by the oggngprocedure earlier mentioneci so that the dust sources a.bsorb the liquidfrom the ga stream or, in other words. so that the liqud is depositedfrom the gas stre;em onto the sources of dust.

In another method of applicetion the liquicl is introduced. into the manat high ponts and allowed to run by gravity to 10W ponts where theexcess can be drawn 01. An examination of mains treated in this marmershows that my composition has greatly improved elirnbing properties.

Another method comprses inserting a, long length of hose into the mainwith a spray at its end, or with a plurality of sprays distributed alongits length, and pumpng the treeting liquid nto the hose whilewithdrawing the hose either continuously or ntermittently orother- Wise,or while the hose remans stetibnary.

In the last three methods of application service on the line need not beinterrupted Dustsources become coated with the treating liquid. 'I'hewet- Figure 2 is a cross-section on line 2-2 of Figure 1.

In the drawing the g.s main i 6 is shown with 2. joint comprising bellli and spigot l2 fitting wthn said bel1 and spaced therefrom. In -thespace between the bell and the spigot is celluloslc fiber pecking I'3which may be terrecl or untarred, and a, seel M of leed or othersuitable meterial or holding the paokng in place. The treating lquid i4as illustrated is bing run through the main by gravty. It contacts thebottom of the rnan and any deposits accumuleted thereon. It alsocontacts the paeking at space i which space is left between the spigotand the shoulder of the bell to provide for expanson and eontraction dueto temperature changes. "Ihe packing absorbs the liquid at I 6 and theliquid climbs and is carried up in the packing as shown by the outergroup of arrows in Figure 2. If one or more substance capable ofswelling the packing such as ethylene glycoldiethylene glycol, monomethyl ether ofethS/lene glycol, mono methyl ether of diethylene glyland glycerine is present thepackin is swoll to substantially the sameextent as with water. 'I'he treatng liquid also climbs up the metalwalls of the main as illustrated by the inner group of arrows in Figure2 to coat dust sources in additon to those along the bottom of the main.

The bulk of the treatng liquid, of course, remains in the main onlyduring the time that.its flow from the point of introducton to the pointof removal Which usually is the nearest drip.

Any ether means for applying the 'treating liquid to the packing end/orto the interor of the conciuit may be employed. For instance, in thecase of large diameter mains the level of the liquid i5 inay be raisedor may be made to fill the entire main if desired, or the spray orfogging methods may be employed.

In the case of a. welded main, or ether main havng jonts in whchcellulosie fiber packing is not present, the treatment becomesprimarilyone of clust leying. Likewise, whenmy mono phenyl ether of ethyleneglycol is employed with these non-cyclic high boiling aliphatic alcoholswhich are ncapable of swelling the paokin such as certain of thosedsclosed in my parent applica# tion, the treatment becomes moreessentally one lected from a group consisting of ethylene glycol,

of dust layng regardless of the type of main treated, except in so faras a 1qud seal is formed in the interstices of the packng.

Whi1e the inventon has been described in connecton with gas mains it isto be understood that it is applicable to any part of a gas distributionsystem wherein similar problems may arse. It is also to be understoodthat the various agents referred to herein may be used ether In the pureor commercially pure form, or in any other suitab1e form including thecommercial and crude forrns.

It is to be understood that the above particu- 1ar descripton is by wayof illustration and that changes, omssons, addtions, substtutions,end/or modiflcatons might be made within the scope of the claims withoutdeparting fromthe spirit of the invention.

For instance, other tar penetratng agents or other sutable material maybe added in addition to my monophenyl ether of ethylene glycol.

The terms comprises and comprising are used in the claims in theirusually accepted meanings which do not exclude other steps or thepresence of substances other than these specifica1ly rected.

I claim:

1. A method for reducing gas lea.kage through cellulosic fibrous packingin a joint of a gas distributon system, comprising impregnatng saidpacking with a cellulosic fiber swellng agent seleeted from a groupconsistlng of ethylene g1ycol, diethylene g1ycol, mono methyl ether ofethylene glycol, mono methyl ether of diethylene glycol, and glycerineby bringing said agent nto contact with said packing in the presence ofmono phenyl ether of ethylene glycol.

2. A method for laying dust in the interlor of a gas distributon conduithavng dust dposits along the bottom therecf, comprsng envelopng saiddust deposts with a dust laying liquid sedethylene glycol, mono methylether of ethylene glycoi, mono methyl ether of dethylene glycol, andglycerine by brngng said 1iqud nto contact with said dust sources in thepresence of mono phenyl ether of ethylene g1ycol.

3. A joint in a gas distributon systern comprisng spaced cooperatingelements, cellulosc fibrous packing such as jute and hemp between saidcooperating elements, positioned to form a sca1, and a liqud mixtureabsorbed by said packing, said liquid mixture comprising mono phenylether of ethylene glyco1 and at least one of a group consisting ofethylene glycol, diethylene glycol, mono methyl ether of ethyleneg1ycoi, mono methyl ether of dethylene glycol, and glycerine.

4. A joint in a gas distribution system comprsng a be1l, a spgotPositioned within and spaced from said bel1 to form en annular space, anannu 1ar ring o cellulosc fibrous packing in said annular space andcontinuo1sly contacting said be1l and spigot on its outer and innerperipheries respectively, and a. liquid mixture absorbed by said packingsaid liqud mixture comprising mono phenyl ether of ethylene glycol andat least one of a group conssting of ethylene glycol, diethylene glycol,mono methYl ether of ethylene glyc0l, mono methyl ether of diethyleneglycol,

s.nd glycerine.

5. A method for trezting th interior of a gas distribution system whchcomprises applying to the interor of said system a lqud mixturecomprsing a non-cyclic high boilng aliphatic alcoho1, and monophenylether of ethylene glycol.

6. A gas condut having interor dust sources wetted down with a liquidmixture comprising a non-cyclic high boiling aliphatie. alcohol, andmonophenyl ether of ethylene giycol.

JOHN R. SICEEN.

